First Step… Check the weather. In particular look at the wind, because on inland waters, wind against current = chop. And… chop can be very uncomfortable and sometimes dangerous because the distance between waves is very short, whereas swell with a long period of time between waves… i.e. greater than 12 seconds may not be as uncomfortable nor as dangerous. 6 foot chop with a 3 second period is way more uncomfortable and more dangerous than a 6 foot swell at 12 seconds. So… check the wind… then check against the second step: the current
This is a snip from a program, Windy.com. It is very good at predicting wind strength and direction and many other parameters such as ocean swell and period (time between swells). The blue color in this case, and according to the scale is in the 0 to 5 knot range, i.e. low velocity. The data an also be viewed in tabular format, but for passage planning I like the overall picture and the colors are very helpful. It goes purple, blue, green, yellow,… then shades of red. We are no longer sailors so we don’t like red. In fact most sailors don’t like red… unless you are racing downwind. The lines which actually move in the direction of the wind on the smart phone program are running from the SW 90 degrees to our course. So… really… no wind to speak of predicted during our proposed passage and it is not running against whatever currents are predicted along our course.
Just for giggles, this is a snip of the Gulf of Alaska, and although it is pretty mild for the Gulf of Alaska at 25+ knots, the reddish tones tell the story compared to the greenish tones around Port Browning in the Gulf Island… around 10 knots or so
The Second Step of any passage in the Pacific Northwest: Determine status of currents on passage route. The best two resources that work together are:
They are easy to use. Go to the date / time in the Waggoner Tables:
0900, Chart 3:
We are looking for currents that go in our direction or at least are perpindiular to our course. Arrows against the course mean that we will not make the best speed over ground (SOG) and will will also waste fuel.
Big arrows mean big currents… little arrows, weaker currents
The Navy Passage arrows are a bit larger
Chart 7: Big arrows in Navy Passage at 1300. So… leaving Ganges at 1100 (check out time at the marina), the first patch of open water, Captain’s Passage has the current going in the direction we want to go. Also, between 0900 and 1300, Navy Passage shows the current going in our direction. Leaving Ganges at 1100 we will be in Navy Passage at… 1215 or so and we will get a 1 to 2 knot “boost” in SOG. We’ll see if science is on our side…
Chart plotter view on left, Navigation Plotter view on right. Great Northern is coming up on the last barrier island before entering Captains passage.
The navigation light on the end of the last small barrier island (red, right, returning) which means when leaving … the red should be on the port (left) side of the boat…
Chart Plotter view of the course between Salt Spring Island and Prevost Island
Just past the light at the South end of Salt Spring Island looking North through Trincomali Channel which separates Salt Spring Island (left) and Galiano Island (right). It doesn’t get more tranquil than this in late November… It pays to look at the wind data before departure.
Eyes forward and looking East you can see Active Pass (in the middle of the picture) that separates Galiano Island (on the left) and Mayne Island (on the right). It is a major ferry / commercial ship passage to the Strait of Georgia
Swiveling the boat Southeast towards our goal you can now see Navy Passage, the small gap to the left of the ferry (yes… that white blob is a large ferry). On the right of Navy Passage is North Pender Island. To the left is Mayne Island. The misty island you see through Navy Passage is Saturna Island:
Just Past Prevost Island with another view down Southeasterly Swanson Channel
And… We can see the current boost to our SOG we were looking for. Speed Through Water = 7.9 Kt; Speed Over Ground = 9.4 Kt; Push: 1.5 Kt; Faster passage; Saving fuel! Science in action!
Rocky Islet and two empty oil tankers anchored in Plumper Sound. North Pender Island on the right, Saturna Island on the left. When empty, tankers anchor to conserve on fuel and operating expenses awaiting their next delivery. They are seen in the oddest places…
The last turning buoy of our mini-passage before entering Port Browning. Razor Point, North Pender Island on the right, and South Pender Island on the left.
The hard right at the last buoy…